中文摘要：

建立了超声萃取-气相色谱/质谱法同时测定土壤中3种典型季胺盐化合物十二烷基三甲基氯化胺（DTAC）、十六烷基三甲基溴化胺（CTAB）、双十二烷基二甲基氯化胺（DDAC）的分析方法。采用电子轰击（EI）-选择离子检测（SIM）进行定量分析,特征离子为m/z 58,212。考察了萃取剂种类、辅助萃取剂直链烷基苯磺酸（LAS）浓度、萃取剂pH值（0.5～7.0）、萃取次数（1,2,3）以及净化柱成分对萃取效率的影响。最佳萃取条件为,以甲醇为萃取剂,以HCl调至pH 3.5, LAS浓度为40μg/L,超声萃取2次,每次10 mL 甲醇,20 min,萃取液采用中性氧化铝柱净化。3种目标化合物的线性范围在0.02～2.0 mg/L之间；方法检出限为1.2～4.5μg/kg。以此方法测定南方某矿区尾矿渣及周边水稻土、赤红壤等样品,目标化合物的含量在0.24～0.41 mg/kg之间,不同加标水平（0.2,0.5和1.0 mg/kg）回收率在76%～113%之间,相对标准偏差在1.1%～12.9%之间。

英文摘要：

An analytical method was developed for the simultaneous extraction and determination of three quaternary ammonium compouds （ QACs） in soil samples using ultrasonic extraction and gas chromatography-mass spectrometry（ GC-MS） . The qualitative and quantitative analysis of the three analytes dodecyltrimethyl ammonium chloride （ DTAC） , cetyltrimethyl ammonium bromide （ CTAB） and didodecyldimethyl ammonium chloride （ DDAC） were conducted by application of EI mass spectra and selected ion monioring （ SIM ） . Characteristic ions of the QACs were m/z 58 （ DTAC and CTAB） and m/z 212 （ DDAC） . To achieve optimum extraction efficiency, several impact factors including types of extractants, pH of extraction, concentration of linear alkylbenzene sulfonates （ LAS） , extraction times and content of purification column were investigated. Methanol with pH 3. 5 and 40 μg/L LAS solution were selected as extractant. Soil sample was extracted by treated methanol each 10 mL for 20 min every time. Extract of the soil sample was purified by neutral alumina column with 4 cm in length and 1cm in diameter, and then was determineted by GC-MS. Good linear relationships of all the three QACs were obtained in the range of 0. 02-2. 0 mg/L. The limits of determination （LOD, S/N=3） was 1. 2-4. 5 μg/kg. The method was used to analyse real soil samples （ paddy soil, lateritic red soil, and ore tailings） collected from a mining district in south China. Results of determination exhibited the concerntrations of the three analytes in real soil samples ranged from 0 . 24 mg/kg to 0. 41 mg/kg, and their recoveries ranged from 76% to 113% with relative standard deviations （ RSD） of 1. 1%-12. 9% in three different spiked concentrations of 0. 2, 0. 5 and 1. 0 mg/kg.